PSLE A bookstore is having a book sale.
The 1st book is at 15% discount.
The 2nd book is at 40% discount.
The price of the 2nd book should be equal or lower than the price of the 1st book.
Anna and Ian each bought two books at the sale.
- Anna's books were priced at $12 and $21. How much less did she pay for the 2nd book than the 1st book?
- Ian paid a total of $38.20 for his two books. He paid $9.40 more for the 1st book than for the 2nd book. What was the price of the 1st book before discount?
|
1st book |
2nd book |
Total amount |
Original price
|
100% $21 |
100% $12 |
|
Discount |
- 15% |
- 40% |
|
Sale price |
85% |
60% |
? |
(a)
Selling price of the 1st book
= 85% x 21
=
85100 x 21
= $17.85
Selling price of 2nd book
= 60% x 12
=
60100 x 12
= $7.20
Amount that Anna paid less for the 2nd book than the 1st book
= 17.85 - 7.20
= $10.65
|
1st book |
2nd book |
Total amount |
Original price |
100% |
100% |
|
Discount |
- 15% |
- 40% |
|
Sale price |
85%
|
60%
|
|
Compare 1st book and 2nd book |
1 u + $9.40 |
1 u |
$38.20 |
(b)
Sale price of the 1st book = 1 u + 9.40
Sale price of the 2nd book = 1 u
Total amount that Ian paid
= 1 u + 9.40 + 1 u
= 2 u + 9.40
2 u + 9.40 = 38.20
2 u = 38.20 - 9.40
2 u = 28.80
1 u = 28.80 ÷ 2 = 14.40
Sale price of the 1st book
= 1 u + 9.40
= $23.80
85% of the price = $23.80
100% of the price =
23.8085 x 100 = $28
Selling price of the 1st book before discount = $28
Answer(s): (a) $10.65; (b) $28